The same can’t be said over the absence of two Pro Bowl defensive starters: Outside linebacker Justin Houston, who enters the final year of his contract, and Brandon Flowers.

Chiefs coach Andy Reid wasn’t available to the media following the afternoon practice. But team spokesman Ted Crews response of “camp is voluntary camp” effectively addressed Houston’s and Flowers’ absences.

Veteran inside linebacker Derrick Johnson reinforced that message.

“This is a voluntary minicamp or voluntary OTAs,” Johnson said when asked about his teammates’ absence. “So it’s one of those things where you worry about the guys that are here. I’m a guy that’s been through this. It’s not a big deal.”

While Johnson said he’s been in touch with Houston and Flowers, he wouldn’t acknowledge if he knew the duo wouldn’t be present for the first day of OTAs.

“I can’t say that,” Johnson said. “I don’t know anything about that. We’re friends off the field, but when it comes to the business part, I stay out of that just because nobody gets in mine.”

Frank Zombo took Houston’s place at outside linebacker with the first-team defense, while second-year pro Marcus Cooper took Flowers’ place.

The Chiefs set of voluntary OTAs are May 27-29, June 3-5 and June 10-13. The mandatory minicamp is June 17-19.

Some could view the current absence of star players such as Houston and Flowers as a distraction, but quarterback Alex Smith didn’t believe that would be the case in Kansas City.

“I’m worried about playing quarterback,” Smith said. “To be totally honest, I’ve got enough on my plate and I think that’s the same for everybody here.”

Injury updates

Tight end Travis Kelce stood on the sidelines with a baseball cap and did not participate in team activities. The second-year pro is returning from microfracture knee surgery.

Left tackle Eric Fisher (shoulder) did light work at the beginning of the team activities before moving to the sideline to observe the rest of the afternoon. Fisher “is doing some things, but his shoulder, he’s still kind of working back from that,” a team spokesman said.

Tuesday offered an early look at how the competition heading into training camp could be with Allen Bailey filling Jackson’s spot, Joe Mays, who signed a free-agent deal in March, taking Jordan’s place and Husain Abdullah getting the nod over Sanders Commings at free safety.

Also of note, starting cornerback Sean Smith changed jersey numbers from 27 to 21, Dunta Robinson’s former number. The Chiefs released Robinson in February.

Offensive line shuffle

With Eric Fisher (shoulder) sitting out the 11-on-11 drills, Donald Stephenson moved from right tackle to left. Jeff Linkenbach took over at right tackle.

Rishaw Johnson was with the first-team at right guard.

Tryout signs

The Chiefs announced Tuesday morning the signing for offensive tackle Ryan McKee. To make room on the roster, the Chiefs waived offensive tackle Chandler Burden.

McKee, who measures 6-foot-6, 308 pounds, was one of 35 players invited for a tryout during the weekend’s rookie minicamp.

He played collegiately at Southern Mississippi, and then entered the league as an undrafted free agent with the New York Jets in 2009. He also spent time with the St. Louis Rams from 2010-12.

McKee spent 2013 with the North Carolina football coaching staff as a graduate assistant.

Looming contract battles?

A reported explanation of Houston’s absence from the first day of voluntary OTAs:

#Chiefs star OLB Justin Houston skipped OTAs today. I’m told he wants a new contract. He has a year left on his rookie deal at $1.4M.